The proposed research is designed to identify and describe laryngeal arthritic changes. It is hypothesized that rheumatoid arthritic and normal subjects will differ in measures of acoustic vocal noise, relative spectral energy, fundamental frequency range, and vocal fold movement. Vocal noise and relative spectral energy will be evaluated using computer-assisted residue inverse filtering. FORTRAN programs will be used to derive the residue inverse signal and six acoustic features: pitch perturbation quotient, amplitude perturbation quotient, coefficient of excess, pitch amplitude, inverse filter spectral flatness, and residue signal spectral flatness. In addition, the FM recorded signals will be analyzed with sensitive fundamental period perturbation indices: mean perturbation, linear trend, and deviation from linear trend. Fundamental frequency range information will be acquired using an analog fundamental frequency extraction system. The extreme upper and lower limits of the fundamental frequency range will be compared across groups. Vocal fold vibratory details will be studied using an ultrahigh-speed photography system. Abductory-adductory vocal fold movements will be tracked frame-by-frame, with computer software computing measures of vocal fold vibratory behavior, glottal width during /h/, and glottal voicing/devoicing transitions in /ihi/. A listening experiment will allow acoustical and physiological measures to be compared with perceived dysphonia. Experienced listeners will rank the arthritic patients according to perceived harshness, breathiness, and hoarseness. Relationships among perceived dysphonia, vocal noise, and vocal fold movement dynamics will be evaluated. It is hoped that alerting health care professionals to the prevalence and nature of laryngeal rheumatoid arthritis will lead to recognition and treatment of a voice disorder which has frequently gone undetected. Furthermore, the findings are expected to yield new insights into laryngeal biomechanics, contributing substantially to our knowledge of vocal fold excursion and crioarytenoid and cricothyroid joint dynamics. This study also will provide experimental paradigms and observational tools for our future investigations of the aging larynx.